import org.opensearch.index.query.QueryBuilders;
import org.opensearch.search.SearchHit;
import org.opensearch.search.sort.SortBuilder;

public class ESSourceReader implements DocumentReader {
    private static final Logger logger = LogManager.getLogger(ESSourceReader.class);

    protected final Queue<Map<String, Object>> queue = new ConcurrentLinkedQueue<>();
    protected final AtomicBoolean isFinished = new AtomicBoolean(false);

    }

    @Test
    public void test_getLimitDocNum() throws Exception {
        assertEquals(10, ESSourceReader.getLimitDocNum(100, 10, -1));
        assertEquals(25, ESSourceReader.getLimitDocNum(50, 50, -1));
        assertEquals(10, ESSourceReader.getLimitDocNum(50, 50, 10));
    }

    @Test
    public void test_sort() throws Exception {
        String indexName = "test-index";

        final SystemHelper systemHelper = ComponentUtil.getSystemHelper();
        suggester.indexer().indexFromDocument(() -> {
            final ESSourceReader reader = new ESSourceReader(ComponentUtil.getSearchEngineClient(), suggester.settings(),
                    fessConfig.getIndexDocumentSearchIndex());
            reader.setScrollSize(fessConfig.getSuggestSourceReaderScrollSizeAsInteger());

suggester.indexer().index(new SuggestItem(new String[] { "検索", "エンジン" }, readings, 1, tags, roles, SuggestItem.Kind.DOCUMENT));
```

### Add suggest documents from source of index

```java
DocumentReader reader = new ESSourceReader(
    client,
    suggester.settings(),
    "contentIndexName",
    "contentTypeName");
suggester.indexer().indexFromDocument(reader, 2, 100).getResponse();
```

### Add suggest document from queryLog

        bulkRequestBuilder.execute().actionGet();
        runner.refresh();

        CountDownLatch latch = new CountDownLatch(1);
        AtomicInteger numObInputDoc = new AtomicInteger(0);
        ESSourceReader reader = new ESSourceReader(client, suggester.settings(), indexName);
        reader.setScrollSize(1000);

        suggester.indexer().indexFromDocument(() -> reader, 1000, 100).then(response -> {